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# Characteristic Data Formats

Constants for identifying the data format of characteristic values.

## Discussion

Expect to find one of these values in the [`format`](/documentation/HomeKit/HMCharacteristicMetadata/format) property of a characteristic’s metadata.

## Topics

### Booleans

[`let HMCharacteristicMetadataFormatBool: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatBool)

Indicates that the characteristic has Boolean values.

### Strings

[`let HMCharacteristicMetadataFormatString: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatString)

Indicates that the characteristic has string values.

### Signed Values

[`let HMCharacteristicMetadataFormatInt: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatInt)

Indicates that the characteristic has `int` values.

[`let HMCharacteristicMetadataFormatFloat: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatFloat)

Indicates that the characteristic has `float` values.

### Unsigned Integers

[`let HMCharacteristicMetadataFormatUInt8: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatUInt8)

Indicates that the characteristic has unsigned 8-bit integer values.

[`let HMCharacteristicMetadataFormatUInt16: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatUInt16)

Indicates that the characteristic has unsigned 16-bit integer values.

[`let HMCharacteristicMetadataFormatUInt32: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatUInt32)

Indicates that the characteristic has unsigned 32-bit integer values.

[`let HMCharacteristicMetadataFormatUInt64: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatUInt64)

Indicates that the characteristic has unsigned 64-bit integer values.

### Data

[`let HMCharacteristicMetadataFormatData: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatData)

Indicates that the characteristic has data blob values.

[`let HMCharacteristicMetadataFormatTLV8: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatTLV8)

Indicates that the characteristic has TLV8 values.

### Collections

[`let HMCharacteristicMetadataFormatArray: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatArray)

Indicates that the characteristic has array values.

[`let HMCharacteristicMetadataFormatDictionary: String`](/documentation/HomeKit/HMCharacteristicMetadataFormatDictionary)

Indicates that the characteristic has dictionary values.


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